Investigation of Physical Properties of Cobalt Nanoparticles Synthesized via Pulsed Laser Ablation in Liquid

Abstract

Cobalt nanoparticles with 99.99% purity were synthesized from cobalt flakes using pulsed laser ablation in liquid with a Nd:YAG laser. Two laser wavelengths (532 and 1064 nm) and various laser fluences (30, 40, 50, and 60 J/cm²) were employed, with 300 pulses at a 6 Hz repetition rate. The UV-visible spectroscopy revealed optical absorption peaks in the range of 270-297 nm. The x-ray diffraction analysis confirmed that the cobalt nanoparticles exhibit a cubic crystalline structure. Atomic force microscopy showed that increasing laser fluence reduced the particle size. Field-emission scanning electron microscopy images revealed nanoparticles with an average diameter of approximately 18.17 nm. These results indicate that laser fluence plays a crucial role in controlling the size and physical properties of the cobalt nanoparticles produced.